Self-cleaning spark-plttg



PATENT OFFICE.

EUGENE KRAFT, OF SPOKANE, WASHINGTON.

Specification of Letters Patent.

SELF-CLEANING SPARK-PLUG.

Patented Feb. 22, 1921.

Application filed June 17, 1918. Serial No. 240,506.

To all whom it may concern:

Beit known that I, EUGENE KRAFT, a citizen of Russia, having taken out initial naturalization papers of citizenship in the United States, and residing at Spokane, in the county of Spokane and State of lVashington, have invented new and useful Improvements in Self-Cleaning Spar Plugs, of which the following is a specification.

This invention relates to explosion en gines and has to do more particularly with an improved ignition device therefor.

In the explosion engines, especially the large stationary type where low grade hydro-carbon is most generally employed, a great deal of difiiculty is experienced in preventing the spark terminals from fouling.

This is not only due to the fact that a constant speed stationary engine operates for longer periods of duration per average day,

7 as compared to an explosion engine on an auto, but also because of the large volume and low grade'fuel which is generally emplo ed.

l ow it is one of the objects of this invention to dispose the spark terminals not only in the path of the mixture flowing to the cylinder, but to dispose at least one of the terminals in such relation to the path of flow that the mixture will play upon and clean an entire circumferential area of such terminal so as not only to maintain the same clean, but further and more important, to prevent any deposits from ever lodging on such terminal.

In the larger size of engine of this character it is not always possible to admit a sufficient mixture through the spark plug, and therefore, my invention provides for an auxiliary intake valve together with means for operating the auxiliary valve in cynchronism with the usual spark valve.

My invention will be more fully described in connection with the accompanying drawing and will be more particularly pointed out in and by the appended claim.

In the drawing I have shown in vertical section, the upper portion of a cylinder equipped with the devices of my invention.

Like characters of reference designate similar parts throughout the diflerent figures of the drawing.

As shown, 6 designates a cylinder having In the cylinder head is an auxiliary intake valve closure 9 which cooperates with the seat I) to control admission through auxiliary intake pipe 6 The closure 9 has a stem 9 extending through a stufling box I) and actuated by spring o to normally seat said closure. An to exhaust valve closure 7: controls egress through an exhaust pipe is, and has a valve 75 operated by cam lever r, pivoted at 1*. Stem g is operated by a lever 39 pivoted at p and having an extension m for engagement with the stem d of the main spark plug valve d. The closure d is normally actuated toward a closing position by a spring 1. This lever 39 is actuated by a cam rod in and has an adjusting screw n to vary the extent of opening movement of the closure d. It will thus be seen that the auxiliary and main intake closures 7c and d will be operated in synchronism. I

It is a feature of my invention to provide a self-contained spark plug housing which 1 have shown at j, and which is-capable of bodily detachment from the cylinder 6. The head 0 of the casing is also ca )able of detachment from the section j. pipe 70 delivers the carbureted mixture to the chamber s, the flow of which is controlled by the closure (Z. The mixture flows into chamber 6 and through passage 6 into the combustion chamber 11. One of the spark terminals, indicated at 7", projects laterally of and into the passage t and toward the axis thereof. The remaining terminal 6 has its lower end in suitable arcing relation to the terminal f.

Now one of the novel features of this invention is to dispose the'terminal e, in such relation, and preferably axially of the passage t, so that the mixture in its natural flow in passing into the combustion chamber will play upon an entire circumferential area of the terminal 6. It will be seen that a considerable length of the terminal 6 is disposed centrally the )assage 2? so that this play of the mixture t ereon will function to prevent even the start of any deposits, much less their accumulation. Furthermore, the upper peripheral surface of the terminal 7' will likewise directly face the flow of the mixture. With this novel arrangement, the interruption to continued operation is largely if not wholly avoided as regards such interruptions which are directly due to the fouling of the spark terminals.

Because the terminals are always clean,

they can be disposed in closer relation than heretofore, and thus a low tension magneto or a relatively Weaker battery may he used.

It is believed the advantages and utility of my invention will be clearly understood from the foregoing description and while I have herein shown one specific form of my invention, I do not Wish to be limited thereto except for such limitations as the claim may impart.

. I claim In a self cleaning spark plug device for explosion engines the combination with an engine cylinder having an intake passage for admission of the carbureted mixture maintain an entire circumferential portion 25 of said terminal free from deposits.

EUGENE KRAFT. Witnesses:

JOHN M. CANNON, LILLIE OARGILL. 

